package com.sunhao.gulimall.search.service.impl;

import com.alibaba.druid.util.StringUtils;
import com.alibaba.fastjson.JSON;
import com.sunhao.common.to.es.SkuEsModel;
import com.sunhao.gulimall.search.config.GulimallElasticSearchConfig;
import com.sunhao.gulimall.search.constant.EsConstant;
import com.sunhao.gulimall.search.service.MallSearchService;
import com.sunhao.gulimall.search.vo.SearchParam;
import com.sunhao.gulimall.search.vo.SearchResult;
import lombok.extern.slf4j.Slf4j;
import org.apache.lucene.search.TotalHits;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.*;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * 描述：MallSearchServiceImpl 类的用途
 * 日期：2024/12/2
 */
@Slf4j
@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Autowired
    private RestHighLevelClient client;

    @Override
    public SearchResult search(SearchParam param) {
        //动态构造出查询的DSL语句

        SearchResult result = null;
        //1.准备检索请求
        SearchRequest searchRequest = buildSearchRequest(param);
        try {
            //2.执行检索请求
            SearchResponse response = client.search(searchRequest, GulimallElasticSearchConfig.COMMON_OPTIONS);

            //3.分析检索结果并封装成我们需要的格式
            result = buildSearchResult(response,param);
        } catch (IOException e) {
            e.printStackTrace();
        }

        return result;
    }

    /**
     * 构造检索结果
     * @param response
     * @return
     */
    private SearchResult buildSearchResult(SearchResponse response,SearchParam param) {

        SearchResult result = new SearchResult();

        //1.查询的所有商品
        SearchHits hits = response.getHits();

        List<SkuEsModel> list = new ArrayList<>();
        if (hits.getHits()!=null && hits.getHits().length > 0)
        {
            for (SearchHit hit : hits.getHits()) {
                String sourceAsString = hit.getSourceAsString();
                SkuEsModel esModel = JSON.parseObject(sourceAsString, SkuEsModel.class);

                //判断是否按关键字检索，若是就显示高亮，否则不显示
                if (!org.springframework.util.StringUtils.isEmpty(param.getKeyword())) {
                    //拿到高亮信息显示标题
                    HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
                    String skuTitleValue = skuTitle.getFragments()[0].string();
                    esModel.setSkuTitle(skuTitleValue);
                }

                list.add(esModel);
            }
        }
        result.setProducts(list);


        //2.当前所有商品涉及的属性信息
        List<SearchResult.AttrVo> attrVos = new ArrayList<>();
        //获取属性信息的聚合
        ParsedNested attrsAgg = response.getAggregations().get("attr_agg");
        ParsedLongTerms attrIdAgg = attrsAgg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attrIdAgg.getBuckets()) {
            SearchResult.AttrVo attrVo = new SearchResult.AttrVo();
            //1、得到属性的id
            long attrId = bucket.getKeyAsNumber().longValue();
            attrVo.setAttrId(attrId);

            //2、得到属性的名字
            ParsedStringTerms attrNameAgg = bucket.getAggregations().get("attr_name_agg");
            String attrName = attrNameAgg.getBuckets().get(0).getKeyAsString();
            attrVo.setAttrName(attrName);

            //3、得到属性的所有值
            ParsedStringTerms attrValueAgg = bucket.getAggregations().get("attr_value_agg");
            List<String> attrValues = attrValueAgg.getBuckets().stream().map(item -> item.getKeyAsString()).collect(Collectors.toList());
            attrVo.setAttrValue(attrValues);

            attrVos.add(attrVo);
        }

        result.setAttrs(attrVos);

        //3.当前所有商品涉及的品牌信息
        List<SearchResult.BrandVo> brandVos = new ArrayList<>();
        //获取到品牌的聚合
        ParsedLongTerms brandAgg = response.getAggregations().get("brand_agg");
        for (Terms.Bucket bucket : brandAgg.getBuckets()) {
            SearchResult.BrandVo brandVo = new SearchResult.BrandVo();

            //1、得到品牌的id
            long brandId = bucket.getKeyAsNumber().longValue();
            brandVo.setBrandId(brandId);

            //2、得到品牌的名字
            ParsedStringTerms brandNameAgg = bucket.getAggregations().get("brand_name_agg");
            String brandName = brandNameAgg.getBuckets().get(0).getKeyAsString();
            brandVo.setBrandName(brandName);

            //3、得到品牌的图片
            ParsedStringTerms brandImgAgg = bucket.getAggregations().get("brand_img_agg");
            String brandImg = brandImgAgg.getBuckets().get(0).getKeyAsString();
            brandVo.setBrandImg(brandImg);

            brandVos.add(brandVo);
        }
        result.setBrands(brandVos);

        //4.当前所有商品涉及的分类信息
        //获取到分类的聚合
        List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
        ParsedLongTerms catalogAgg = response.getAggregations().get("catalog_agg");
        for (Terms.Bucket bucket : catalogAgg.getBuckets()) {
            SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
            //得到分类id
            String keyAsString = bucket.getKeyAsString();
            catalogVo.setCatalogId(Long.parseLong(keyAsString));

            //得到分类名
            ParsedStringTerms catalogNameAgg = bucket.getAggregations().get("catalog_name_agg");
            String catalogName = catalogNameAgg.getBuckets().get(0).getKeyAsString();
            catalogVo.setCatalogName(catalogName);
            catalogVos.add(catalogVo);
        }

        result.setCatalogs(catalogVos);

        //5.分页信息-页码
        int pageNum = param.getPageNum();
        result.setPageNum(pageNum);

        //6.分页-总记录数
        long total = hits.getTotalHits().value;
        result.setTotal(total);
        //7.分页信息-总页码
        int totalPages = (int) total % EsConstant.PRODUCT_PAGESIZE == 0 ? (int)total / EsConstant.PRODUCT_PAGESIZE : (int)total / EsConstant.PRODUCT_PAGESIZE + 1;
        result.setTotalPages(totalPages);

        List<Integer> pageNavs = new ArrayList<>();
        for (int i = 0;i < totalPages;i++)
        {
            pageNavs.add(i);
        }

        result.setPageNavs(pageNavs);

        //TODO 分页系统 一百多页 连续显示五六页
        return result;
    }

    /**
     * 构造检索请求
     * @return
     */
    private SearchRequest buildSearchRequest(SearchParam param) {
        //构建检索语句
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();

        //查询：模糊匹配、过滤
        //1.bool查询 逻辑组合
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        //1.1 must
        if (!StringUtils.isEmpty(param.getKeyword())) {
            boolQuery.must(QueryBuilders.matchQuery("skuTitle", param.getKeyword()));
        }
        //1.2 filter 三级分类
        if (param.getCatalog3Id() != null)
        {
            boolQuery.filter(QueryBuilders.termQuery("catalogId",param.getCatalog3Id()));
        }
        //1.2 filter 品牌id
        if (param.getBrandId()!=null && param.getBrandId().size() > 0)
        {
            boolQuery.filter(QueryBuilders.termsQuery("brandId",param.getBrandId()));
        }

        //1.2 filter 属性
        //TODO 属性在前台没有显示
        if(param.getAttrs() != null && param.getAttrs().size() > 0){

            param.getAttrs().forEach(item -> {
                //attrs=1_5寸:8寸&2_16G:8G
                BoolQueryBuilder nestedboolBuilder = QueryBuilders.boolQuery();

                //attrs=1_5寸:8寸
                String[] s = item.split("_");
                String attrId=s[0];
                String[] attrValues = s[1].split(":");//这个属性检索用的值
                nestedboolBuilder.must(QueryBuilders.termQuery("attrs.attrId",attrId));
                nestedboolBuilder.must(QueryBuilders.termsQuery("attrs.attrValue",attrValues));

                NestedQueryBuilder nestedQuery = QueryBuilders.nestedQuery("attrs",nestedboolBuilder, ScoreMode.None);
                boolQuery.filter(nestedQuery);
            });

        }

        //1.2 filter 库存
        if (param.getHasStock() != null)
        {
            boolQuery.filter(QueryBuilders.termQuery("hasStock",param.getHasStock()==1));
        }


        //1.2 filter 价格区间 range
        //todo 价格区间查询有问题 ????
        /**
         *
         */
        if (!StringUtils.isEmpty(param.getSkuPrice()))
        {
            RangeQueryBuilder query = QueryBuilders.rangeQuery("skuPrice");
            String[] s = param.getSkuPrice().split("_");
            if (s.length == 2)
            {
                query.gte(s[0]).lte(s[1]);
            }
            else if (s.length == 1)
            {
                if (param.getSkuPrice().startsWith("_"))
                    query.lte(s[0]);
                if (param.getSkuPrice().endsWith("_"))
                    query.gte(s[0]);
            }
            boolQuery.filter(query);

        }


        //组合所有查询条件
        sourceBuilder.query(boolQuery);

        //排序、分页、高亮
        //2.1 排序
        if (!StringUtils.isEmpty(param.getSort()))
        {
            String sort = param.getSort();
            String[] s = sort.split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc") ? SortOrder.ASC : SortOrder.DESC;
            sourceBuilder.sort(s[0],order);
        }

        //2.2 分页
        sourceBuilder.from((param.getPageNum()-1)*EsConstant.PRODUCT_PAGESIZE);
        sourceBuilder.size(EsConstant.PRODUCT_PAGESIZE);

        //高亮
        if(!org.springframework.util.StringUtils.isEmpty(param.getKeyword())){

            HighlightBuilder highlightBuilder = new HighlightBuilder();
            highlightBuilder.field("skuTitle");
            highlightBuilder.preTags("<b style='color:red'>");
            highlightBuilder.postTags("</b>");

            sourceBuilder.highlighter(highlightBuilder);
        }

        //聚合分析
        //1. 按照品牌进行聚合
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg");
        brand_agg.field("brandId").size(50);
        //1.1 品牌的子聚合-品牌名聚合
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg")
                .field("brandName").size(1));
        //1.2 品牌的子聚合-品牌图片聚合
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg")
                .field("brandImg").size(1));

        sourceBuilder.aggregation(brand_agg);

        //2. 按照分类信息进行聚合
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg");
        catalog_agg.field("catalogId").size(20);

        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));

        sourceBuilder.aggregation(catalog_agg);

        //2. 按照属性信息进行聚合
        NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
        //2.1 按照属性ID进行聚合
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
        attr_agg.subAggregation(attr_id_agg);
        //2.1.1 在每个属性ID下，按照属性名进行聚合
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        //2.1.1 在每个属性ID下，按照属性值进行聚合
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));
        sourceBuilder.aggregation(attr_agg);

        log.info("构建的DSL语句 {}",sourceBuilder.toString());
        SearchRequest request = new SearchRequest(new String[]{EsConstant.PRODUCT_INDEX}, sourceBuilder);
        return request;
    }
}
